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The most rediculious DIY exhaust cut out ever

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Old 02-09-2014, 12:41 AM
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Jim Stainer
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Default The most rediculious DIY exhaust cut out ever

There is a fine line between moron and genius and I'm pretty sure I know which side this one falls on...

The saga starts when I noticed a a 3 1/2" elbow that happened to be sitting on the counter at NAPA.
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That sparks an idea. This would be so much better than my 2 1/2 manual cut out that doesn't flow very well.
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So I hunt on ebay for at least a 3" throttle body. It took a little time and a best offer and score at 22 bucks shipped!
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Then out comes the welder to put them together.
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With a header flange I attach this monster to the side of the muffler. I also put a scoop at the back to direct air down the cut out.
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I try to hide it so it won't show.
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Now how to make it move I happen to have a control cable laying around so I route it up to the drivers seat.
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PROBLEM! The cable control is really hard to pull and won't keep the throttle flap open with the spring in it. When I put less pressure on the spring it won't seal shut. Time for a plan B and where intelligent design kind of fall apart...

I cut apart a Camaro door to get the motor out.
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Then welded said motor in the trunk with a hunk of cable welded to the gear.
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I ran the cable through a handy hole in the floor, over a pulley and to the throttle - er a no the cut out.
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Wire it all up the a Camaro power window switch
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And voila an electric cut out for 34 bucks. Check out the video if you want hear how it works. You can jump ahead to 48 seconds if you want to skip seeing the above photos again.


Last edited by charchri4; 06-04-2014 at 12:34 PM.
Old 02-09-2014, 09:01 AM
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Great bit of re-purposing. I likeit.
Old 02-09-2014, 10:49 AM
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Rube Goldfarb would be proud.
Old 02-09-2014, 03:47 PM
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Ghetto fantastic! LOL!!
Old 02-10-2014, 07:28 AM
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Be honest, you watched a lot of Macgyver back in the day right...A+ for the effort!
Old 02-10-2014, 09:15 PM
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I wonder,,,,you said "PROBLEM! The cable control is really hard to pull and won't keep the throttle flap open with the spring in it. When I put less pressure on the spring it won't seal shut."

I wonder if a higher quality twist lock cable, along with a lighter spring and or perhaps changing the arc of the actuator at the valve body would make a manual actuator work,,,I wonder,,,,,
Old 02-11-2014, 08:56 AM
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Jim Stainer
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Common sense would be to send 200 bucks to summit and do it right! LOL but like so many parts of this build the most fun is to pull up a tire to take a load off grab a beer and say OK how can I make this work with the stuff in my junk pile. This one was right up there with building a brake cooler system out of an old air pump and just as nuts which is why I had to post it.

When I first started looking for a throttle body I wanted a drive by wire one that I could just wire up and control but they were all too pricey and I doubted they would take the heat very long. When the cable didn’t work I looked at locking cables thinking I could use a very light spring because it would lock both in and out. But again most such cables are 40-60 dollars and I wasn’t beat yet.

I took apart the Camaro traction control motor because it is a push pull set up but the way it is designed it would not have lived long as a valve controller because the motor would have to be pushing all the time. I looked at the heater blend door actuator which would have had a plus because at no vacuum I could have it open up. But it would take one the size of a brake booster to work against the amount of exhaust pressure even at part throttle. And on the process goes. Something that will pull or push pretty hard and not let go till I tell it to. Oh hey just like a power window does!

Last edited by charchri4; 02-12-2014 at 12:32 PM.
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